Many situations in the practice of clinical medicine produce temporary and reversible lung failure. In this situation, hypoxia, or inadequate oxygenation of the blood may be life threatening or fatal. An incomplete list of the clinical settings in which this might arise includes:
(A) Newborn premature infants PA1 (B) Heart and lung surgery patients PA1 (C) Fulminent pneumonia PA1 (D) Legionnaires disease PA1 (E) Toxic shock syndrome PA1 (F) Severe emphysema PA1 (G) Lung transplants PA1 (H) Adult respiratory distress syndrome PA1 (I) Acute pulmonary embolus
The current treatment techniques available for acute life threatening hypoxia include positive pressure ventilation which requires the passage of a per nasal or per oral endotracheal tube, and attachment to a pressure controlled or volume controlled machine ventilator. The problems associated with this procedure include difficulty in initiation, trauma to the nasal or pharyngeal tissue and structures, errors of intubation of the esophagus thus further compromising ventilations; inadvertant intubation of the right main stem bronchus with hyperexpansion of the right lung and collapse or atelectasis of the left lung, damage to the pharynix and vocal cords, on rare occasions erosion through the inominate artery and exanguanation, and not the least, rather extreme discomfort to the patient.
A second form of support in the hypoxic circumstance is with a membrane oxygenator. This is primarily used during a surgical procedure which requires temporary cardiac arrest, such as open heart surgery (i.e. coronary bipass surgery, cardiac valve surgery, and repair of congenital cardiac abnormalities). This procedure requires a highly skilled, well organized team, and can be used for an extremely short period of time, usually for a matter of two to six hours. This procedure produces increasingly severe changes in the blood components, secondary to membrane trauma, hemolysis of red cells, platelet lysis, release of clotting factors, and large volume anticoagulant therapy. All of these may lead to severe tissue toxicity, massive hemorrhage, and cellular destruction if the procedure is not terminated within the time limits stated.
Clearly, an alternative form of tissue and blood oxygenation would be extremely beneficial and, in many of the aforementioned cases, life saving.